The present invention relates to food warming devices, and in particular to cabinets wherein large quantities of prepackaged, prepared foods can be heated to the desired temperature and maintained at this temperature during serving.
In institutions where food is served, such as schools, hospitals and cafaterias, the meals are often prepared in advance, prepackaged and mechanically refrigerated. In order to be able to handle the large number of meals so that they may be served at about the same time, it is necessary that the packages of food be brought to the serving temperature quickly and in bulk, and then maintained at the serving temperature during the serving operation.
One of the problems connected with a meal preparation and serving operation such as this is bringing the foods up to the temperature quickly enough, while at the same time heating the food packages uniformly so as to avoid some of the meals being uncooked whereas others are overcooked or burned. Many prior art cabinets have been constructed to receive a large number of packages of food and then heat them by the circulation of heated air, but the heating has not always been sufficiently uniform to maintain the desired temperature throughout the cabinet. This is an especially difficult problem where a large number of food packages must be heated, because some of the packages are nearer the walls of the cabinet, and will therefore be heated more quickly than those at the center. Even with good circulation of the heated air, the food packages nearest the cabinet walls will reach a higher temperature than those at the center, and this may result in overheating of the outermost packages of food.
A further problem with some prior art heating cabinets is that the heated air is conducted to the interior of the cabinet in such a manner that a substantial amount of heat is lost through the duct work. This is especially true in cabinets where the heating and blower units are mounted beside the food well where it is possible for the heat to radiate upwardly and be lost. Although locating the heating elements below the food well will eliminate much of the radiant heat loss, this can cause hot spots on the bottom of the food well so that the lowermost packages may be overheated or even burned.